1. Senior Design SD1107 Solar Module Observation Device Team Leader: Collin Howe, CprE Webmaster: Jacob Rasmuson, CprE Communications: Arthur Fiester, CprE Team Member: Alex Rannow, EE Team Member: Timothy Fox, EE Academic Advisor: Dr. Ahmed E. Kamal Client: PowerFilm Solar, Inc. Client Representative: Brad Jensen SD1107 - Solar Module Obeservation Device

2. Agenda Executive Summary Project Overview Modules Sensing Circuitry Microcontroller Android Application Development Schedule and Cost SD1107 - Solar Module Obeservation Device

3. Problem Statement PowerFilm wishes to have a remote measurement device that can communicate with a smartphone application over a Bluetooth interface. Benefits of this device include the following: Access to information about charging/discharging rates to give the user an in-depth look into the status of the device. Logging capabilities which will allow users to track the solar module’s efficiency. Estimated charging times which will allow the user to track the charge progress of the device. Real-time data which will help determine optimal placement angles to place the solar module. Executive Summary SD1107 - Solar Module Obeservation Device

4. Bluetooth-connected voltmeter/ammeter device, interfaced with solar panel and storage battery. Smartphone application to receive data and to display battery life and charge time Device settings must be modifiable by the smartphone application when connected A 1 in 2 footprint PCB Operating temperature range of -40°C ~ 105°C Must be able to measure voltages of 0-15.5VDC, and currents 0-0.5A Powered by solar panel’s storage battery Multiple power states (Active, Standby, Sleep) Maximum production cost of $20/unit Must log data over specified time if so configured by user Requirements SD1107 - Solar Module Obeservation Device

5. Smartphone app with graphing capability to display data (zoom) USB and/or GSM connectivity User-defined sampling rates (1/2 second – 1 hour intervals) Smartphone app able to control multiple solar devices Tabbed user interface Wishes SD1107 - Solar Module Obeservation Device

6. Development Time Access to development community Experience with programming with the microcontroller and Android application Device Small size of PCB (less 1 in 2 ) Low power consumption (Must draw no more than 50mA of current in full operation) Maximum production cost ($20) Constraints and Limitations SD1107 - Solar Module Obeservation Device

7. TI MSP430F247 microprocessor with PAN1315 Bluetooth radio connected to sampling circuitry Integrated Bluetooth antenna inlaid in PCB Mobile phone application running on a Bluetooth-enabled Android phone Android application programmed in Java using Eclipse IDE Solution SD1107 - Solar Module Obeservation Device

8. System Overview SD1107 - Solar Module Obeservation Device

9. Losing a team member Unable to utilize Bluetooth PCB integration Component damage during fabrication Design is incorrect and requires rework Risk Management SD1107 - Solar Module Obeservation Device

10. MSP430+PAN1315 vs. CC2540 vs. Other All-In-One MCU/Radio: The MSP430 + PAN1315 option is somewhat more expensive than some other options Much better support community Complete system and demo/evaluation equipment Uses universally-accepted Bluetooth2.1+EDR (The CC2540 used newer, backwards-incompatible Low Energy Bluetooth that has yet to be implemented in any end user devices.) Component Antenna vs. PCB Inlaid antenna Component Antenna provided pre-engineered Bluetooth 2.4GHz antenna Component antenna adds expense (No extra monetary expense for using PCB Inlaid antenna from TI Designs) Inlaid PCB Antenna requires relatively large footprint on our PCB Technology/Tradeoffs SD1107 - Solar Module Obeservation Device

11. Current Sensing: 20 mΩ sense resistor in series with lines of interest Voltage drop across resistor fed into 200 V/V differential amplifier Output of amplifier fed into ADC of microcontroller Use ratio of 0.25A/V to calculate current Voltage Sensing Accomplished by voltage divider Fraction of Vcc inputted into ADC of microcontroller 2.1 V Zener diode placed at ADC for protection Sensing Circuitry: Overview SD1107 - Solar Module Obeservation Device

12. Schematic: Sampling Circuitry SD1107 - Solar Module Obeservation Device

13. Microcontroller: Overview SD1107 - Solar Module Obeservation Device ADC Interface to the Current/Voltage sensing circuits 12 bits of resolution Measure VIA timer interrupt at certain user-defined intervals (1/2 second to 1 hour) Software scaling to actual voltages/currents Bluetooth Radio Control Communicate with TI/PAN1315 Bluetooth Radio over UART Initiate as device using SPP (Serial Port Profile) Communicate through MindTree/TI Bluetooth Stack VIA RTOS (Free Real Time Operating System, open source) Power States Able to lower power state of MSP430 into “standby” and “sleep” modes through software/radio control

14. Microcontroller: Device Concept SD1107 - Solar Module Obeservation Device

15. Microcontroller: Program Structure SD1107 - Solar Module Obeservation Device

16. Schematic: Microcontroller and Bluetooth Transceiver SD1107 - Solar Module Obeservation Device LEDs implemented in prototype only To Current &Voltage sensing circuits To power supply (2V to 3.6V DC)

17. Makes use of Bluetooth on the Android hardware to interface with our device. Communication over GSM and USB are desirable possibilities as well, but might be unfeasible. Must be able to alter the configuration of the monitoring device (such as sampling rates and logging options). Incorporate data from the device into a friendly user interface. Android Application: Overview SD1107 - Solar Module Obeservation Device

18. Android Application: GUI SD1107 - Solar Module Obeservation Device Home Screen Display current status of tethered devices and provide quick access to them. Allow access to application wide variables Device Screen Controls power state and pinging function Displays up-to-date voltages and currents along with a graph of previous data Allows user to set device settings

19. Android Program Structure SD1107 - Solar Module Obeservation Device

20. Testing SD1107 - Solar Module Obeservation Device Module Testing: Determine if each module is working independently. (Test voltage/current for correct output based on controlled input. Test Android application against previously-implemented SPP terminal device) Integration Testing: Once it is determined that each module is working within respective parameters we will integrate all three modules in a lab environment System testing: Finally the system test will involve system integration between our working device and a testbed solar panel in “real world” conditions.

21. Testing SD1107 - Solar Module Obeservation Device TestModulePreliminary Results Accuracy of measuring voltages and currents.IMM5% error from actual input Battery Capacity/ charging time predictionIMM Range of voltages/currentsIMM1-15.4 volts and 0.01-0.5 amps Input sampling rates(upper bound) via Android parametersIMM, System5 samples/sec with < 1 second propagation delay ADC Input resolutionIMM, System2 decimal places Current consumption of deviceIMM, MCActive mode: < 300 Microamp Standby mode: < 1 Microamp Hibernate mode: < 1 Microamp Data rate between application and MCMC, App Perform properly and consistently under durability temperature range test SystemRange : -40 to 105 Power mode state change via AndroidMC, Android<1 second propagation delay Compatible with multiple and different android devicesApp Off switch safely powers down deviceSystem, MC Power surge protectionIMM, MC, SystemOperates within normal parameters Independent data updating to Android functionality is consistently working MC, App, SystemWorks when connection denoted by the application Consistent Connection/ Disconnection via AndroidMC, App Bluetooth rangeMC

22. Completed Tasks Project plan & design document Technology Selection Detailed Design including all schematics Acquired components and development tools Tested and verified the sampling circuitry Android Application development Remaining Schedule Module development and testing Establish Bluetooth connectivity Integrate sampling circuitry with microprocessor End product testing and debugging Schedule SD1107 - Solar Module Obeservation Device

23. Cost Estimation End Product ComponentPartQuantityPrice Sense ResistorRL16T.0206CT-ND20.88 Op AmpNJM271011.62 Zener DiodeFLZ3V9B10.08 Protect Zener DiodeBZX84C2V4S20.44 Bluetooth RadioPAN131518.71 MicrocontrollerMSP430F24713.41 Total$15.86 Development ComponentPartPrice Experimenter boardRL16T.0206CT-ND150 Evaluation ModulePan 131599 Debugging InterfaceFLZ3V9B99 Total$348 SD1107 - Solar Module Obeservation Device

24. Questions? SD1107 - Solar Module Obeservation Device 01010001 01110101 01100101 01110011 01110100 01101001 01101111 01101110 01110011 00001101 00001010 ?